The normal range of blood pressure in the morning, midday and evening is 100~120mmHg for high pressure and 60~80mmHg for low pressure, and the difference in blood pressure within a day should not exceed 20mmHg. Normally a person’s blood pressure is highest around 10 o’clock in the morning and 5 o’clock in the afternoon, and lowest around 1 o’clock in the morning, but the variation in blood pressure within a day should be within 20mmHg. A single blood pressure reading above the normal range may be normal, and three consecutive blood pressure measurements on a non-same day above 140/90 mmHg are required to be diagnosed as high blood pressure. A person’s blood pressure is not static. It rises during times of emotional excitement and falls slightly during times of calmness, so people with high blood pressure should pay attention to adjusting their emotions.